ACT Reading: Evaluate Author Credibility to Judge Argument Strength and Potential Bias

Test 1: Experience and expertise. Does the author have direct knowledge of the topic? A cardiologist writing about heart disease is credible. A celebrity writing about medicine is not. Test 2: Acknowledgment of complexity. Does the author admit nuance or only present one side? A credible author might say "While this approach works, it has limitations..." An uncredible author might say "This is the only solution." Test 3: Transparency about potential bias. Does the author disclose conflicts of interest? Example: "Full disclosure: I work for a pharmaceutical company, but research shows..." is more credible than hiding the conflict. Credible authors demonstrate expertise, acknowledge complexity, and are transparent. Authors who fail these tests may be credible on other topics but not on their stated subject.

Why it matters: A persuasive passage from an uncredible author is less reliable than a less eloquent passage from a credible expert. The ACT tests whether you distinguish between good writing and trustworthy writing, encouraging critical evaluation of source authority.

Mistake 1: Judging credibility by eloquence or passion instead of expertise. An author can write beautifully and be wrong. A climate scientist with poor writing skills is more credible on climate science than an eloquent journalist without expertise. Separate writing quality from source authority. Mistake 2: Assuming credibility transfers across topics. A credible economist may be uncredible on medicine. Check whether the author's expertise applies to the specific topic discussed. Always ask: Is this author's background relevant to this topic? Has the author disclosed potential biases?

On the ACT, if a question asks about the author's credibility, re-read for evidence of expertise (qualifications, experience), honesty (acknowledging limitations), and transparency (disclosing conflicts). Use these three tests to build an evidence-based assessment.

Author 1 (excerpt): "As a cardiologist with 20 years of experience, I can tell you that exercise is crucial for heart health. That said, for patients with certain conditions, extreme exercise can be harmful. I always recommend consulting your doctor." Assessment: Test 1 ✓ (cardiologist, 20 years experience). Test 2 ✓ (acknowledges nuance: "extreme exercise can be harmful"). Test 3 ✓ (transparent: "consult your doctor" shows awareness of limitations). Verdict: Highly credible. Author 2 (excerpt): "Everyone agrees that diet fads are the only way to lose weight. As a weight-loss influencer, I know this truth. My program has no downsides." Assessment: Test 1 ✗ (influencer, not a nutritionist or doctor). Test 2 ✗ ("only way," "no downsides" show no nuance). Test 3 ✗ (does not disclose potential profit from selling the program). Verdict: Low credibility. For each author, apply the three tests and note which are passed and failed, then determine overall credibility.

On the next ACT Reading practice test, find an argumentative passage. Apply the three credibility tests to the author. Note whether credibility assessment changes your view of the argument's strength. By test day, you will instinctively evaluate author credibility and factor it into your answers about argument quality.

Credibility questions appear 1-2 times per reading section and test whether you read with healthy skepticism instead of passive acceptance. This skill is essential for college success, where evaluating sources is central to research and writing. Students who assess credibility answer argument and bias questions with evidence-based reasoning instead of intuition, earning points that other students miss because they do not question author authority.

This week, find two argumentative articles on the same topic but from different sources (an expert and a non-expert). For each, apply the three credibility tests. Compare which author is more trustworthy and why. By test day, credibility assessment will be automatic, and you will answer questions about author authority and bias with confidence grounded in systematic evaluation.