Wireless carriers are urging the Federal Communications Commission (FCC) not to impose aggressive new regulations aimed at protecting the privacy of cellphone users.

In filings with the FCC on Friday, the companies argued that voluntary guidelines are preferable to mandatory rules for how they must handle their customers’ personal information.

The FCC opened a proceeding in May on what it should do to better protect the privacy of cellphone users, and asked for comments from the public.

The commission noted that because of technological advancements, people’s phones can now collect increasingly personal information, such as the websites they visit, the contents of their text messages and even their physical locations.

The cellphone companies came under fire when a computer researcher revealed late last year that many of them use a software called Carrier IQ that collects detailed data about how people use their phones.

The companies said they only used Carrier IQ to analyze general information about the performance of their phones and networks.

In a filing on Friday, CTIA, the wireless industry’s trade group, warned the commission not to adopt new regulations aimed at restricting the use of network diagnostic tools like Carrier IQ.

“Such rules are unnecessary and would actually harm consumers by hamstringing providers in their ability to improve service quality, especially in these times of wireless spectrum capacity constraints,” the group wrote.

CTIA argued that the FCC actually lacks the legal authority to regulate privacy issues that are not directly related to telecommunications networks. So the privacy of text messages, pictures and emails stored on mobile devices is outside the commission’s authority, according to CTIA.

Verizon acknowledged the importance of protecting its customers’ privacy, but said the FCC should allow the Commerce Department to take the lead on addressing the issue.

The National Telecommunications and Information Administration (NTIA), a Commerce Department agency, is currently leading talks between privacy groups and companies about how to better protect people’s privacy online.

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