The Senate Ethics Committee “severely admonished” Senator Robert Menendez on Thursday for accepting gifts from a wealthy doctor while using his position as a senator to promote the doctor’s personal and financial interests.

It also ordered Mr. Menendez, a New Jersey Democrat, to repay the market value of all improper gifts he has not already repaid.

The admonition stems from the same actions for which Mr. Menendez was indicted in 2015. His trial — in which the doctor, Salomon E. Melgen, was a co-defendant — ended with a deadlocked jury in November 2017, and the federal government chose not to retry Mr. Menendez. In its letter of admonition, the Ethics Committee acknowledged that the trial “did not result in a conviction,” but wrote, “The criminal system, however, neither enforces nor supplants the Senate’s rules or standards of conduct, and the committee’s action stands independent from that result.”

The committee’s three Republicans and three Democrats found that from 2006 to 2013, Mr. Menendez “knowingly and repeatedly accepted gifts of significant value from Dr. Melgen without obtaining required committee approval” and “failed to publicly disclose certain gifts as required by Senate rule and federal law.” The gifts included private flights and nights at luxury hotels, among them a villa in the Dominican Republic.