Chicago
33 N. Lasalle Street
Suite 1900
Chicago, IL 60602
Suite 1900
Chicago, IL 60602
Colleen Costello is a highly skilled insurance law attorney who has successfully litigated, mediated, and managed insurance coverage disputes across the United States. Her experience includes handling claims involving professional liability, commercial general liability, umbrella and excess commercial general liability, commercial property, business interruption, extra expense, commercial auto, trucking, technology, and accident and health policies.
With over 22 years of experience representing insurance industry clients, Colleen has handled coverage issues from inception through trial, including numerous appeals. She has represented clients in federal and state courts across more than 25 states and the Virgin Islands.
Colleen has extensive experience in handling extra-contractual and bad-faith disputes in multiple jurisdictions. She has also represented U.S. and U.K.-based carriers in a wide range of first-party property coverage matters, including disputes related to mold, hurricanes, and other natural disasters. Clients routinely ask Colleen for her counsel on third-party coverage matters, such as construction defects, personal and advertising injury, product defects, and more.
Recognizing the inherent risks and costs of litigation, Colleen collaborates closely with her clients to avoid lawsuits by providing an early evaluation of coverage issues and potential exposures and proactively resolving coverage disputes before the commencement of litigation. Her strategic approach and in-depth knowledge of insurance law make her a trusted advisor for insurance industry clients seeking effective resolution of complex coverage disputes.
Colleen was selected by her peers for inclusion in the 2025 and 2026 editions of The Best Lawyers in America® for her insurance practice.
Secured a significant ruling involving an $8,000,000 judgment. The court ruled that our client had no duty to indemnify under the policies.
Successfully investigated and negotiated settlement in the U.S. Virgin Islands under a first- party property policy following a propane gas explosion at a resort that caused significant property damage to a luxury rental property.
Successfully handled multiple disputes in California concerning coverage for habitability lawsuits against California hotels and other properties involving the Oakland Landlord-Tenant Municipal Code, California Civil Codes Sections 940, 1941 and 1942, Health & Safety Code Sections 17920, 19210 and 13133.7 asserting claims of breach of implied warranty of habitability, negligence, and violation of proposition M among other claims.
Won summary judgment motion in Wisconsin state court where the question was whether the “complete operation doctrine,” as codified by a Wisconsin statute applied to a trucking coverage dispute, where the policy was issued in Illinois and the insured was registered in Illinois through the unified carrier registration system.
Obtained summary judgment in favor of a client in Illinois involving a liquor liability policy coverage of a multi-million-dollar default judgment entered against the insured nightclub for negligence in failing to prevent injuries to two patrons.
Prior results cannot and do not guarantee or predict a similar outcome with respect to any future matter that we or any lawyer may be retained to handle.
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