The Colorado Supreme Court ruled on Monday that plaintiffs’ lawyers can use allegations made elsewhere to bolster their own clients’ claims, so long as the attorney first performs some degree of investigation into the “borrowed” assertions.

Under Colorado’s rules for civil cases, attorneys must attest that the complaints they file are well-grounded in fact to the best of their “knowledge, information, and belief formed after reasonable inquiry.” But what if a lawyer can make their case stronger by importing allegations from other legal proceedings involving the same defendant? Do they have to personally speak with witnesses — who may be unnamed or confidential — who made the allegations there?

Not necessarily, concluded the Supreme Court.

By “recognizing that the extent of investigation necessary in a given litigation is highly fact dependent, we decline to adopt a bright-line rule precluding a party from copying allegations in related litigation unless counsel speaks to the witnesses,” wrote Justice Richard L. Gabriel in the April 6 opinion. “It simply may not be possible for counsel to do so. Instead, we conclude that counsel must conduct a sufficient investigation to support the allegations contained in a complaint, at least on information and belief.”

In the underlying case, Dean Houser sued CenturyLink and its directors, alleging that the telecommunications company violated federal securities law by failing to publicly disclose deceptive charging practices at the time of its merger with Level 3 Communications, Inc.

After a trial judge dismissed Houser’s original complaint, the Court of Appeals reinstated it, and Houser amended the lawsuit to include allegations of CenturyLink’s conduct drawn from multiple states’ attorney general investigations and other litigation. Houser’s attorneys attested they had reviewed federal filings, press releases, earnings calls, media reports, and had discussions with lawyers in the other civil proceedings.

After CenturyLink pointed out Houser’s attorneys had imported his allegations from elsewhere, Boulder County District Court Judge Dea M. Lindsey refused to consider those portions of the complaint and she dismissed the lawsuit. But a three-judge Court of Appeals panel decided the practice of “borrowing plausibility” is acceptable so long as some investigation takes place.

The rule mandating that lawyers undertake a reasonable inquiry before making a legal filing “does not require plaintiff’s counsel in such circumstances to speak directly with the confidential witnesses,” wrote Judge Steve Bernard. Instead, the investigative steps taken by Houser’s lawyers were sufficient.

The CenturyLink defendants appealed to the Supreme Court, arguing that the Court of Appeals had cleared the way for Colorado to become a haven for “copycat” lawsuits that “parrot” allegations made in other courts.

“This is beyond untenable — it places defendants at the mercy of lawsuits premised on a glorified game of telephone,” argued the Securities Industry and Financial Markets Association, weighing in to support CenturyLink.

According to the Court of Appeals, “literally, the lawyers in this case can borrow the allegations of lawyers in another case that are not before the court,” Frederick R. Yarger, representing the CenturyLink defendants, told the Supreme Court at oral arguments. “I don’t think it’s ever acceptable to take it on faith from another lawyer.”

Ultimately, the Supreme Court disagreed that copying allegations is prohibited under any circumstance. Instead, wrote Gabriel, Houser’s lawyers had documented the specific actions they took before including information from other sources. A reasonable investigation, even if it does not include interviewing witnesses directly, can combat the disadvantage plaintiffs may face at the outset of a civil lawsuit.

In “many cases, essential facts are in the hands of civil defendants and may not be available to plaintiffs,” noted Gabriel.

He also disagreed that endorsing the practice of borrowing allegations would lead to an explosion of copycat lawsuits filled with dubious assertions.

“To the contrary, we believe that trial courts in this state and others have served — and we have every confidence will continue to serve — as appropriate gatekeepers to ensure that lawsuits that do not satisfy the requirements to survive motions to dismiss will be resolved properly and expeditiously,” Gabriel wrote.

The case is CenturyLink, Inc. et al. v. Houser.